Sexual self-denial, instead of leading to sublimation, may lead to nervous disorder when the erotic tension, failing to find a natural outlet and not sublimated to higher erotic or non-erotic ends in the real world, is transmuted into an unreal dreamland, thus undergoing what Jung terms introversion; while there are also the people already referred to, in whom immature childish sexuality persists into an adult stage of development it is no longer altogether in accord with, so that conflict, with various possible trains of nervous symptoms, may result.

Even a broad category such as introversion is like Silly Putty once life gets hold of it: a "genetically shy" child whose parents gently encourage her to get herself into the sandbox and mix it up with other kids is more likely to outgrow her shyness by age 12 than a shy child whose parents take her trait as a given.